Pianoforte-agraffe.



PATBNTED OCT. l0, 1905.

C. P. BLINN.

PIANOFORTE AGRAFPE.

APPLIoATIoN FILED JUNE 19, 1005.

CHARLES P. BLINN, OF BOSTON, MASSACHUSETTS.

Specification o1" Letters Patent.

Patented Oct. 10, 1905.

Application led June 19, 1905. Serial No. 265,923.

To all whom it may concern:

Be it known that I, CHARLES P. BLINN, of Boston, in the county of Sudolkand State of Massachusetts, have invented certain new and usefulImprovements in Pianoforte-Agrades, of which the following is aspecification.

This invention has for its object to provide a pianoforte-agrade adaptedto support the string or strings engaged with it without liability ofbeing indented by the said string or strings.

Ordinarily a pianoforte-agrade, which is usually made of brass, isformed so that the string bears with considerable force against themetal of the agrade, the result being that the agrade is so indented bythe vibrations of the string that an objectionable buzzing sound occursat the agrade when the string is vibrating. Moreover, the tension of thestring is decreased by the indentation of the agrade, so that it isthrown out of tune.

l overcome the above-recited objections by the improvement which I willnow proceed to describe and claim.

Of the accompanying drawings, forming a part of this specification,Figure l represents a side elevation showingmyimproved agrade and asectional view of a portion of the frame of a pianoforte. Figs. 2 and 3represent elevations of the agrade removed from the frame. Fig. 4Lrepresents an enlarged section on line t L of Fig. 3.

The same reference characters indicate the same parts in all thefigures.

My improved agrade comprises the body portion 5, having a screw-threadedshank 6 to engage a threaded socket formed for its reception in theframe of the pianoforte. In one side of the body of the agrade is formeda recess 7, extending across the body, the upper portion of the agradeprojecting over the recess and being provided with a'seat 8, whichoverhangs the recess 7.

The agrade is provided with one or more string-oriiices 9, three beingshown in the present ease. These oridces extend from the surface of theagrade which forms the inner end of the recess 7 to the opposite side ofthe agrade, as shown in Fig. 4:. Each orifice 9 is made of considerablygreater diameter than the string l0,which passes through the orifice.

l2 represents a rest, which is a short piece of hard metal, preferablyiron or steel, and is formed to closely dt the seat 8, The rest l2 ispreferably of cylindrical form, and its diameter is such that a stringbearing against its under side will be supported entirely by the restand will exert no appreciable pressure upon the wall of the orifice 9through which it passes. Preferably the string will be entirely out ofcontact with the wall of the orifice; but whether this is the case ornot the support adorded by the rest will prevent the string' fromexerting suiiicient pressure on the portion of the agrade through whichit passes to cause indentation of the relatively soft metal of theagrade by the vibrations of the string, the agrade being ordinarily madeof brass.

The rest l2 is detachable from the agrade and is held in the positionshown in the drawings bythe tension of the string, which presses theagrade against the seat 8.

The described improvement prevents any liability of wear or indentationof the agrade tending to vary the tension and tune of the string' orcause a buzzing sound where the string passes through the agrade.

It will be seen that the rest presents a smooth rounded surface of hardmetal to the string which permits the string to render or move endwisemore freely on the agrade in turning than would be the case if thebearing of the string were on the brass body of the agrade. Hence theturning of the string is edected more easily and satisfactorily thanwhen the ordinary agrade is employed. Moreover, when two or more stringsare passed through each agrade the rest insures a uniform height of thestrings, whereas in the ordinary agrade there is liable to be a slightvariation in the height of the strings owing to the didiculty ofdrilling two or more holes at exactly the saine height. Uniformity inthe height of the strings is very desirable, as a slight variation willcause a corresponding Variation in the effect of the blows ofthetension, and preventing indenting Contact he- IO hammers on the strings.tween the string and the body of the agi-atie. I cla1mln testimonywhereof I have ai'ixed my sig- A pianoforte-agrade having` a recess inone nature in presence of two witnesses. side, the upper end of therecess forming a seat overhanging the recess, a sti'ing-apeitu1'eextending through the agraife from the innei side of the recess and arest formed as a separate piece held against the seat by the stringCHARLES P. BLINN.

Vtnesses:

C. F. BROWN, E. BATCHELDER.

